Molar tube lock

ABSTRACT

A molar tube having a first face portion that is adapted to be adhered to a molar tooth, a second face portion, and a mesial-distal length dimension. There is a body portion disposed on the second face portion of the base portion, and the body portion comprises an upper portion and a lower portion. The body portion further comprises a lumen that is adapted to receive an archwire, wherein the lumen has an axis which substantially coincides with the mesial-distal length dimension of the base portion. The body portion further comprises a boss comprising a threaded bore that is adapted to receive a setscrew, wherein the threaded bore has an axis. The axis of the threaded bore intersects with the mesial-distal length dimension to form an angle of any degree between 15 degrees and 55 degrees, including every degree therebetween. A molar tube according to the invention allows for easy adjustment of the tension in an archwire used in an orthodontic dental treatment, and provides for the painless withdrawal of the archwire at any time during or following the treatment.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a Continuation-In-Part of U.S. patent applicationSer. No. 10/091,089 filed on Mar. 6, 2002, now U.S. Pat. No. 6,733,287,the entire contents of which are herein incorporated fully by referencethereto.

TECHNICAL FIELD

The present invention relates generally to a molar tube, and moreparticularly to a molar tube that is adapted to receive an archwire.More particularly still, the invention relates to a molar tube thatfacilitates the withdrawal or adjustment of an archwire after thearchwire has been employed in an orthodontic treatment. The inventionallows an archwire to be locked in the molar tube, thus preventingslippage.

BACKGROUND

During orthodontic treatment and the use of fixed appliances on theteeth, including brackets for receiving an archwire, molar tubes areemployed to anchor the distal ends of the archwire. The molar tubes aremounted on molar teeth, which constitute the posterior teeth in themouth. Following the placement of the distal ends of the archwire inmolar tubes, it is customary to trim the ends of the wire and then bendthe ends that protrude from the distal ends of the tubes to prevent thearchwire from moving mesially through the tubes which could result inspaces opening mesial to the anchor molars. The archwire is otherwisesecured to brackets on the adjacent posterior and anterior teeth, andtherefore it is important not to allow mesial movement of the archwirewhen the fixed appliances are in place. Additionally, in prior artmethods, the distal ends of the archwire are bent in a direction toprevent the ends from striking/irritating the patient's hard or softtissues, the hard tissues being the enamel surfaces of the teeth, andthe soft tissues being the gingiva or cheek.

During the course of treatment using molar tubes of the prior art, it isoften necessary to remove and replace the archwires with the bent ends.Such a procedure requires straightening the bent ends as much aspossible and then pulling those bent ends mesially through the molartubes. Inasmuch as it is difficult, if not impossible, to completelystraighten the ends of the wires, considerable forces are required towithdraw or pull the wires through the tubes. High amounts of force arefirst required to deflect the end of the wire so it can pass through thetube and second to overcome the friction created by drawing the deformedwire through the length of the tube. This is particularly the case wherefull size rectangular archwires are employed to fit rectangular tubes,wherein the tolerances are ±0.001 inch (0.025 mm). The application ofthe necessary forces to remove archwires having bent ends is often quitediscomforting to the patient. It not only is discomforting by the forcerequired but also because of the duration of that force as the archwireis pulled through the entire length of the tube. The well-being andcomfort of a patient is particularly important as it can relate to theresults achieved during orthodontic treatment.

Heretofore, there have been molar tubes for receiving archwires andhaving flared openings at the mesial end to facilitate the threading ofthe archwire into the tube, such as shown in U.S. Pat. No. 5,556,277.There have also been a number of molar tubes for lip bumpers and headgear having the inlet mesial end enlarged to facilitate the mounting ofa lip bumper or head gear, such as shown in U.S. Pat. Nos. 3,815,238;4,963,092; 5,057,012; 5,151,028; and 5,292,248. It is also known toprovide a bracket that permits limited tipping relative to the archwire,as disclosed in U.S. Pat. Nos. 4,842,512; 4,859,179, and 4,877,398.

U.S. Pat. No. 4,355,975 teaches an orthodontic appliance that comprisesa plate bonded to a tooth. The plate is connected to the main body ofthe bracket. The covering orthodontic cap for fixing the wire isconnected to the main body of the bracket. The cap can be removed fromthe bracket since it is fixed and connected thereto with a connectingpart and elastic connecting device. The bracket or the cap is providedwith a shearing groove that prevents the caps from sliding off andprovides for locking and removal of the cap by simple operations.

U.S. Pat. No. 4,424,032 discloses an orthodontic jaw correctionappliance comprising a positioning means operatively disposed betweenthe upper and lower dental arches. The positioning means includes a pairof cooperatively engaged elements, one of which is associated with onearch and the other of which is associated with the other arch. Theelements are operable as the jaw closes to translate the natural jawclosure force into a corrective force component acting between the twoarches. The improvement for operatively relating one element to itsassociated arch comprises a generally U-shaped splint comprising agenerally U-shaped molded plastic body conforming to the general U-shapeof the associated arch for application to the cusps of teeth thereofincluding molar teeth on laterally opposite sides and all teeth mesialto the molar teeth. There is bonding means disposed on the U-shapedmolded plastic body for bonding the molded plastic body to the cusps ofthe teeth so that the splint acts through the bonding means stabilizesthe molar teeth and all teeth mesial thereto as a unit to effect jawcorrection. The one element and the splint have a point of operativecoupling which is mesial to the point of bonding of the splint to atleast some of the molar teeth.

U.S. Pat. No. 4,988,292 sets forth an abutment for an orthodonticanchorage that is mountable on an osseointegrated dental implant fixturein the same manner as are components which are used to supportprosthodontic restorations. The abutment of the invention is adjustablearound the axis of the implant fixture, and it supports a mount forholding an orthodontic anchor fixed to a buccal or a lingual side of theabutment. The mount is adjustable around an axis running between thebuccal and lingual surfaces.

U.S. Pat. No. 5,057,012 describes a molar tube for a lip bumper or aface bow comprising: 1) a base having a lingually-facing attachingsurface for attaching to a tooth; 2) an elongated,mesiodistally-extending tubular body projecting buccally from the base,wherein the body includes an opening therethrough for receiving thedistal ends of a lip bumper or a face bow, and having an inside lingualwall and an outside buccal wall. The opening is flared from the distalend to the mesial end such that the mesial end is larger than the distalend, and of a size substantially larger than the distal end of a lipbumper or a face bow. The distal end of the opening is round and sizedto closely receive the distal end of the lip bumper or face bow toprovide lateral control. The mesial end is oval and has a verticaldimension adapted to closely receive the distal end of the lip bumper orface bow to control tipping, and the long axis of the oval mesial endextends generally horizontally, whereby insertion of a distal end of alip bumper or a face bow is enhanced.

U.S. Pat. No. 5,071,345 teaches a prefabricated dental crown analoghaving an exterior size and contour to approximate the dimensions andshape of a natural tooth at the site, and an orthodontic wire anchorconsisting essentially of hollow tubular means providing an integralpassage extending mesially-distally through the analog closer to one ofthe exterior buccal or lingual surfaces than to the center thereof, forpassage of an orthodontic wire through the passage whereby the wire maybe anchored with the crown analog. The inventive crown is intended foruse in the mouth of a patient having an endosseous dental implantfixture installed in the patient's jawbone at an edentulous site.

U.S. Pat. No. 5,681,164 discloses and orthopaedic modular assemblycomprising: 1) a housing component of rigid material providing a firstpassage; 2) a second component in the form of a lingual pad supporthaving a first arm adapted to form a snug sliding fit within the firsthousing passage; 3) a second arm extending at an angle to the first arm,and adapted to conform to the line of one side of a patient's mouth; and4) a latch means associated with the housing component, whereby thefirst arm of the second component is held within the first passage ofthe housing component by the latch means and is slidably adjustablerelative to the housing component to any one of a plurality ofpredetermined latched positions.

U.S. Pat. No. 5,727,941 provides an implant arrangement for securing adenture to a jawbone, the implant arrangement comprising: 1) an implantshaft means having a central axis, a first end for insertion into thejawbone and a second end; 2) a securing means including a threaded boreformed at the second end for securing the denture thereto, the threadedbore being inclined with a predetermined angle relative to the centralaxis; 3) an insertion tool means for inserting the implant shaft meansinto the jawbone, wherein the insertion tool means has a central axisand a first end removably connected to the implant shaft forrotationally inserting the implant shaft into the jawbone; and 4) aconnection means formed at the first end of the insertion tool meanswith an inclination relative to the central axis of the insertion toolmeans corresponding to the predetermined angle, the connecting meansremovably interfacing the insertion tool means and the implant shaft,wherein the central axis of the insertion tool means is coaxial with thecentral axis of the implant shaft.

U.S. Pat. No. 6,036,488 shows a pivotal mounting boss assembly forattachment to an orthodontic band for the pivotal mounting boss of anarch expansion appliance comprising: 1) a base casing, including a basesegment for attachment to the orthodontic band, the base segment havingan opening formed therein, the opening disposed to attach an arch wire;2) a body segment being narrower in at least one cross sectionaldimension than the base segment, and the body segment having a threadedbore formed therein; and 3) a screw threadedly engaged in the threadedbore, the screw disposed to attach to an eyelet of an expansionappliance.

U.S. Pat. No. 6,217,323 teaches an orthodontic dental distractor forrapid orthodontic tooth movement into a fresh extraction socket. Thedevice includes: 1) a screw bar and a screw nut fixedly engaged with oneend of the screw bar; 2) a first joint engageable with one end of thescrew bar next to the screw nut and a first hook engageable with acanine band mounted on a canine; and 3) a second joint that isengageable with another end of the screw bar and has a second hookengageable with a molar band mounted on a molar. By turning the screwnut, the screw bar will move the first joint towards the second joint,thus moving the canine rearward toward the molar.

Even where the bent end of an archwire used in conjunction with priorart molar tubes is attempted to be straightened in the mouth, it isvirtually impossible to completely straighten the wire, and thereforewithdrawal of such an archwire from a tube requires the application ofsome force to the tube on withdrawal. That force, as applied to thetooth, results in discomfort to the patient.

It is therefore an object of the present invention to provide a new andimproved molar tube for archwires that significantly decreases oreliminates the required force when removing an archwire from the tube.

A further object of the present invention is to provide a new andimproved molar tube for archwires that reduces the force needed towithdraw a bent archwire from the tube and permits free distal crowntipping of the tooth on which the tube is mounted, thereby favorablycontributing to the results obtainable during treatment.

A further object of the present invention is to provide a molar tube forarchwires that is patient-friendly to reduce the forces required towithdraw a bent archwire from the tube during visits with theorthodontist, thereby reducing patient discomfort.

A further object of the invention is to allow an archwire to be securedto the molar teeth to provide superior anchorage over cinching thedistal ends of the arch wire, i.e., so as to not allow molar teeth todrift forward if so desired. A molar tube lock according to theinvention acts as a molar stop.

Another object of the invention is to provide an alternative means toachieve retraction and closure of spaces mesial to the molar teeth. Witha properly designed archwire and appropriate loops, the molar stop cansecure an activated archwire to close spaces, essentially workingsimilar to a tie back with ligature wire.

Another object of the invention is to prevent the need for omega loopsand other such bends designed as molar stops, to prevent mesial movementof the molar teeth.

Another object of the invention is to enable archwire to be secured toallow for advancement of anterior teeth by locking the archwire to themolar tubes and allowing the archwire to extend slightly in front ofanterior brackets, as in cases of class II, div. II diagnoses. Molarteeth, due to their size and anatomy are generally used for anchorage.Smaller teeth in front are moved essentially because the larger tooth ismore positionally stable to applied forces. Loss of anchorage, orslippage of the molar teeth forward is desirable in some cases. Thus, amolar tube lock according to the invention would not be activated—toallow free movement of the archwire through the tube, i.e., molars moveforward to close space versus anterior teeth moving backward to closethe space. A molar tube lock according to the invention can be usedafterwards, to prevent re-opening of spaces. Thus, the present inventionis universal and can be used in all situations requiring advancementarches, retraction arches, reinforcement of molar anchorages, andprevention of spaces re-opening.

Another object is to provide a molar tube lock that allows the straightwire technique of orthodontic treatment to operate more efficiently.

Other objects, features and advantages of the invention will be apparentfrom the following detailed disclosure, taken in conjunction with theaccompanying sheets of drawings, wherein like reference numerals referto like parts.

SUMMARY OF THE INVENTION

The above-mentioned problem of patient discomfort is solved by thepresent invention wherein a molar tube according to the presentinvention eliminates the need to bend archwires, as is the case whenusing molar tubes of the prior art, and thus inherently eliminates theuse of force otherwise needed to mesially withdraw a bent archwire fromthe tube.

More particularly, a molar tube according to the present inventionincludes a lumen and a threaded boss comprising a threaded hole, whereinthe axis of the threaded hole in the boss is disposed at an angle ofapproximately 45° to the axis of the lumen. Such an arrangement allowsfor the selective securing of an archwire at a desired position/tensionwithin the lumen, while providing control over labiolingual andocclusogingival archwire movement for either round and rectangulararchwires, and also torque control for rectangular archwires. Under suchan arrangement, the force required to mesially withdraw a bent archwirethrough the tube is dramatically reduced, if not wholly eliminated inmost cases.

The amount of initial force to draw the bent end of an archwire into themolar tube of the present invention and the subsequent force thereafterrequired to pull the archwire the full length of the tube and remove itfrom the tube may be reduced to a level of about 0 to 5 percent of whatwould normally be required with a conventional molar tube. This forcereduction translates into enhanced patient comfort.

In its simplest form, a molar tube according to the present inventioncomprises a base portion having a first face portion that is adapted tobe adhered to a molar tooth, a second face portion, and a mesial-distallength dimension. There is a body portion disposed on the second faceportion of the base portion, and the body portion comprises an upperportion and a lower portion. The body portion further comprises a lumenthat is adapted to receive an archwire, wherein the lumen has an axiswhich substantially coincides with the mesial-distal length dimension ofthe base portion. The body portion further comprises a boss comprising athreaded bore that is adapted to receive a setscrew, wherein thethreaded bore has an axis. The axis or centerline of the threaded boreintersects with the mesial-distal length dimension to form an angle ofany degree between 15 degrees and 175 degrees, including every degreetherebetween. The axis or centerline of the threaded bore intersectswith the vertical dimension to form an angle of any degree between about60 and 120 degrees.

BRIEF DESCRIPTION OF DRAWINGS

In the annexed drawings:

FIG. 1 is a perspective view of a molar tube according to the invention;

FIG. 2 is a perspective view of a molar tube according to the invention;

FIG. 3 is an end view of a molar tube according to the invention;

FIG. 4 is a top view of a molar tube according to the invention;

FIG. 5 is a perspective view of a molar tube according to the inventionshowing a cutaway section;

FIG. 6 is a perspective view of a molar tube according to the inventionshowing a cutaway section;

FIG. 7 is a buccal side view of a molar tooth having a molar tubeaccording to the invention affixed thereto; and

FIG. 8 is a top view of a molar tooth having a molar tube according tothe invention affixed thereto.

DETAILED DESCRIPTION

Referring to the drawings and initially to FIG. 1, there is shown amolar tube 10 according to the present invention. Such molar tubecomprises a base portion 11 having a first face portion 52 and a secondface portion 54. The base portion 11 is preferably fabricated accordingto an orthodontic prescription to deliver the correct tip and tonguefeatures when it is subsequently properly secured to the tooth. Thefirst face portion 52 is that surface which may to be bonded to thebuccal side face of a molar tooth, using conventional dental bondingmaterials and methods known in the art as useful for bonding molar tubesto teeth. Typically, the face portion 52 is welded or soldered to a bandthat is then cemented to the molar teeth, as is known in the art;however, direct bonding is also acceptable. Disposed on the second faceportion 54 is a body portion 15 that incorporates the essential featuresof the invention.

One essential feature of the invention is a lumen 17 that is adapted toreceive an archwire that is circular in cross-section. Such lumen 17 islocated within and passes completely through the entire body portion 15in a mesial-distal direction.

According to a preferred form of the invention, there is a second lumen13 that is adapted to receive an archwire which is square or rectangularin cross-section. Such lumen 13 is located within and passes completelythrough the entire body portion 15 in a mesial-distal direction.

According to one preferred form of the invention, the lumens 13 and 17are disposed within the body portion 15 and have axes that are parallelto one another, that is, the axis of lumen 13 is parallel to the axis oflumen 17. However, parallelism of the axes of the lumens is notcompletely essential, as the axes of these lumens with respect to oneanother may be inclined any amount between about 0 and 15 degreeswithout departing from the scope of the invention. The axes of thelumens 13 and 17 are disposed along the center of the lumen in eachcase. The dimension of the body portion 15 in the mesial-distaldirection determines the length of the lumen in each case. Thus, thatportion of each of the axes of the lumens 13 and 17 which is containedwithin the body portion 15 is a finite segment of the axis, which mayconveniently be referred to in each case as the “contained axis” for aparticular lumen. While a preferred form of the invention comprises apair of lumens as described above, one having a circular or ellipticalcross-section and the other having a square or rectangularcross-section, the present invention includes those cases where the bodyportion 15 only includes a single lumen, having either a circular,elliptical, rectangular, or square cross-section.

The body portion 15 also includes a boss portion 25 having a threadedbore (33, FIG. 2) comprising an axis through its centerline disposedtherethrough. The threaded bore 33 is adapted to receive a setscrew 23having threads on its external surface that are complementary to thethreads in the inner portion of the threaded bore 33. The axis of thethreaded bore within the boss portion 25 is disposed to be skew (notparallel, but never intersecting) to the axis of a lumen such as 13 or17. For embodiments when both lumens 13 and 17 are present, it is mostpreferred that the axis of the threaded bore within the boss portion 25is skew to both the contained axes of the lumens, and the axis of thethreaded bore within the boss portion 25 passes between both the axes ofthe lumens 13 and 17. Such an arrangement is particularly beneficial,for cases within the scope of the invention wherein the distance betweenthe centerlines of the lumens 13 and 17 is less is sufficient to enablea securing contact between the end of the set screw (71 in FIG. 2) tocontact an archwire disposed with a lumen 13 or 17 when the set screw isthreaded into the threaded bore of the body portion and tightened.

The body portion also includes a channel 19 at its lower portion alongits mesial-distal direction to which other wares (such as elastics,ligature wires, etc.) known useful in orthodontics may be secured. Thereare also ears 27 a and 27 b that are curvedly contoured to function incooperation with the upper portion 76 of the body 15 to define a channel29 having a semi-circular cross-section to which other wares (such aselastics, ligature wires, etc.) known useful in orthodontics may besecured. This channel 29 has a length dimension L that coincides withthe mesial-distal axis of the body portion 15 and base portion 11.According to a preferred form of the invention, the length dimension ofthe channel 19 coincides in length with the channel 29; however, channel19 may be longer or shorter than channel 29, as dictated by theselection of the contours of the body portion 15. In a preferred form ofthe invention, there is also disposed at the lower portion 74 of thebody portion 15 a hook arm 21, which is beneficial for securing elasticsor other wares known useful in orthodontics to the molar tube of theinvention.

In FIG. 2 is shown a perspective view of molar tube 10 according to oneform of the invention as in FIG. 1 that has been rotated 180 degrees.Here is shown the base portion 11, body portion 15, boss portion 25having threaded bore 33 disposed therein, and hook arm 21. Also shown isthe set screw 23 having an end portion 71 which, in use, securedlycontacts an archwire which is disposed in either of lumens 13, 17, orboth.

FIG. 3 depicts an end view of a molar tube 10 according to one form ofthe invention showing the respective dispositions of various elements ofthe invention, including the base portion 11, body portion 15, lumens 13and 17, circular channel 29, channel 19, hook arm 21, threaded bore 33,boss 15, and set screw 23. The preferred orientation of the molar tubewithin the patient's mouth is indicated by the line G which in this FIG.3 is pointing towards the gumline of the patient. There is also shown inFIG. 3 horizontal ray a which is disposed perpendicularly to thesubstantially planar surface 52 that is adapted to be affixed to thebuccal side of a molar tooth of the patient, and a vertical line B isshown (which coincides in direction with the vertical dimension (height)of the molar tube 10) to define an angle β which a is descriptive of theangle that the centerline of the threaded bore 33 may take on withrespect to the vertical dimension of the molar tube. According to thepresent invention, angle β may be any angle between about 60 degrees and120 degrees, using the line B as a zero reference and measuring theangle β from a location such as point P on line B in FIG. 3. Thus, theaxis or centerline of the threaded bore 33 may be disposed so that itintersects the line B at any angle between about 60 and 120 degrees,including all ranges defined by any two angles residing therebetween.When angle β is 90 degrees, the centerline of the threaded bore 33 isdisposed substantially horizontally with respect to the surface 52 ofthe body portion of a molar tube 10 of the invention, and is alignedwith ray a. When angle β is 60 degrees, the centerline of the threadedbore 33 is disposed to be coincident with the ray C₂ in FIG. 3. Whenangle β is 120 degrees, the centerline of the threaded bore 33 isdisposed to be coincident with the ray C₁ in FIG. 3. According to analternate form of the invention, the axis of the threaded bore 33intersects with the vertical dimension B of the molar tube 10 of theinvention to form an angle of any degree between about 60 and about 100degrees. According to another form of the invention, the axis of thethreaded bore 33 intersects with the vertical reference dimension of themolar tube 10 of the invention as defined by the line B to form an angleof any degree between about 60 and about 90 degrees. Thus, thecenterline of the bore 33 may take on a range of positions with respectto both its orientation with respect to the mesial-distal lengthdimension x of the base portion 11, and the vertical dimension describedby the vertical line B.

FIG. 4 depicts a top view of a molar tube 10 according to one form ofthe invention showing the respective dispositions of various elements ofthe invention, including the base portion 11, body portion 15, bossportion 25 and lumen 17. The threaded bore portion 33 has an axis a, andthe lumen 17 has an axis b. There is an angle α, which represents theangle of intersection between the centerlines of the threaded boreportion 33 and the lumen 17, as viewed from the top of the molar tube10. This angle α may be any angle between about 15 degrees and 175degrees. More preferably α is any angle in the range of between about 30degrees and 150 degrees. It is most preferred that α is any anglebetween 60 degrees and 30 degrees, with an angle α of about 45 degreesbeing most preferred. There is also shown in FIG. 4 the mesial-distallength dimension x of the base portion 11. Thus, it can be seen that theaxis b of the lumen 17 substantially coincides with the mesial-distallength dimension of the base portion 11. For purposes of this inventionand the appended claims “substantially coincides” means that the angleof intersection of the axes b and x is ±20 degrees, on either side oftheir being parallel to one another, and including the case where theyare parallel. According to a preferred form of the invention, this angleof intersection is less than 7 degrees; however any degree between 0 and20 degrees of intersection of these axes is within the scope of thepresent invention. In one embodiment, the axis of the threaded boreintersects with the mesial-distal length dimension to form an angle ofany degree between 15 degrees and 55 degrees.

FIG. 5 depicts a perspective view of a molar tube 10 according to oneform of the invention having an archwire 35 of circular cross-section inplace within lumen 17 and showing the respective dispositions of variouselements (essential and non-essential) of the invention, includingsetscrew 23, boss portion 25, ears 27 a and 27 b, circular channel 29,base portion 11, body portion 15, and hook arm 21. A part of the bossportion 25 is cut away to show how the setscrew 23 securedly engages thearchwire 35 in position against the inner wall of the lumen in which thearchwire is disposed.

FIG. 6 depicts a perspective view of a molar tube 10 according to oneform of the invention having an archwire 37 of square cross-section inplace within lumen 13 and showing the respective dispositions of variouselements (essential and non-essential) of the invention, includingsetscrew 23, boss portion 25, ears 27 a and 27 b, circular channel 29,base portion 11, body portion 15, and hook arm 21. A part of the bossportion 25 is cut away to show how the setscrew 23 securedly engages thearchwire 37 in position against the inner wall of the lumen in which thearchwire is disposed.

FIG. 7 is a view from the buccal side perspective of a molar tube 10according to the invention that is banded or bonded to a molar tooth 41,and also shows archwire 35.

FIG. 8 is a view from the buccal side perspective of a molar tube 10according to the invention that is banded or bonded to a molar tooth 41.

Although the base portion 11 and body portion 15 have been describedherein as separate elements of a molar tube according to the invention,the present invention contemplates the case where the base portion 11and body portion 15 are both of the same construction, as in the case ofwhen a molar tube according to the present invention comprises a singlecasting which includes both base portion 11 and body portion 15.

A molar tube according to the invention may be attached to a bandmounted on a molar tooth for the purpose of anchoring the distal end ofan archwire, or it may be directly bonded to the tooth itself usingbonding agents known in the dental arts for such purposes. The long axisof the molar tube, or the mesial-distally extending axis, issubstantially perpendicular to the long axis of the tooth on which it ismounted. It will be appreciated that when a band is used, it may be ofany suitable type that is preferably made of stainless steel andsuitably cemented to the molar tooth to which a molar tube according tothe invention is affixed. However, the molar tube may also be mounted ona bondable base for bonding directly to a tooth. It should also beappreciated that it is preferable to construct the molar tube ofstainless steel although any other suitable materials may be used. Itwill be appreciated by those skilled in this art that the shape of thebody portion 15 may be other than as illustrated and also that the molartube may be a part of an appliance having other elements such as a tubefor receiving headgear or a lip bumper and which also may include asuitable hook for connecting elastics to other appliances along thearch. The molar tube lock illustrated in FIG. 1 is for a lower leftmolar and would likewise be usable on molar tubes designed for use inthe other three quadrants, i.e., lower right, upper right, and upperleft. Further, it should be appreciated that, as with all suchtooth-mounted appliances, the exterior edges are rounded to enhancetheir comfort in the mouth.

A molar tube of the invention serves to anchor distal ends of anarchwire wherein the archwire would be received within the lumen and,depending upon the amount of archwire material protruding from thedistal end of the tube, usually trimmed. Next, the setscrew is tightenedagainst the archwire within the lumen in which the archwire is disposed.Preferably, the excess wire protruding from the distal end of the lumenis completely trimmed off by shearing. The securing of the archwire inposition using the force applied by the tightening of the setscrewserves to prevent the archwire from moving mesially through the tubeduring treatment that, if permitted, could lead to opening of spacesbetween teeth along the arch. This arrangement also helps to prevent themolar from drifting or moving forward (i.e., it acts as an anchor) whenso desired.

Importantly, it is not necessary that the set screw be tightened in allcases, i.e., it is sometimes desirable to allow the wire to pass andmove freely through the molar tubes. In one sense, a molar tube lockaccording to the invention can be viewed as an adjunct to achieveselected tooth movements and improve efficiency of orthodontictreatments. There are cases where the main goal is not to secure anarchwire in the tube per se because on occasion the wire needs to movefreely in the tube (for example., when retracting anterior teeth, orclosing spaces in this manner). After some space closure has beenachieved, tightening the set screw will secure the arch wire and preventspaces from re-opening. This can be viewed in many cases as being moreadvantageous than binding the distal end of the archwire.

While there are many different arrangements and sizes of buccal tubes,buccal tubes (on the facing) are usually welded to a preformedorthodontic band. Then, the band of the attachment is fitted on thetooth according to size and cemented in position. A molar tube lockaccording to the present invention can be used on a wide variety ofmolar tube configurations in the manners herein described to provide alock for an archwire when desired.

Subsequent to the securing of the distal end of the archwire within alumen of a molar tube according to the invention, it is often necessaryto withdraw the wire from the tube. This necessity may occur during anyor all of the visits that a patient would periodically make with anorthodontist. It is principally at this time that the molar tube of thepresent invention becomes advantageous inasmuch as the force required tomesially withdraw the archwire is substantially reduced or entirelyeliminated by the present invention. This reduction is obtained by thefact that the only force which holds the archwire in position within thetube is that force exerted by the setscrew, which, when relieved,permits the archwire to be freely withdrawn from the lumen in which itresided, because the wire has been allowed to remain straight.

Although in embodiments of the present invention which include aplurality of lumens 13 and 17 which are adapted to receive archwires ofdifferent cross-sectional geometries the axes of the lumens 13 and 17have heretofore been described as being parallel to one another, or asbeing generally parallel to the mesial-distally extending axis of amolar tooth to which a molar tube according to the invention is affixed,the present invention also contemplates embodiments in which thecontained axes of one or more lumens are disposed at an angle withrespect to the mesial-distally extending axis of a molar tooth to whicha molar tube according to the invention is to be affixed. By providingan inclined lumen wall, the tooth may be prevented against mesial crowntipping but can be allowed distal crown tipping. Thus, a second featureof the molar tube of the invention is that it may facilitate a desiredcontrolled degree of distal crown tipping.

From the foregoing, it will be appreciated that the molar tube of thepresent invention increases the well being of the patient by reducingthe discomfort associated with the withdrawal of an archwire from amolar tube. Both the magnitude and the duration of the removal force arereduced. Further, the molar tube of the present invention not onlyreduces archwire withdrawal forces but can also permit distal crowntipping of the molar on which the tube is mounted. In addition, metalfatigue on the wire used is decreased due to there being no necessity tobend the distal ends of the archwire, which in many cases alleviateswire breakage. Arch wire tie backs with ligature wire can also beeliminated.

Consideration must be given to the fact that although this invention hasbeen described and disclosed in relation to certain preferredembodiments, obvious equivalent modifications and alterations thereofwill become apparent to one of ordinary skill in this art upon readingand understanding this specification and the claims appended hereto.Such modifications include the subject matter defined by any combinationof any one of the various claims appended hereto with any one or more ofthe remaining claims, including the incorporation of the features and/orlimitations of any dependent claim, singly or in combination withfeatures and/or limitations of any one or more of the other dependentclaims, with features and/or limitations of any one or more of theindependent claims, with the remaining dependent claims in theiroriginal text being read and applied to any independent claim somodified as if such modified independent claim had been originallyfiled. Such modifications also include combinations of the featuresand/or limitations of one or more of the independent claims with thefeatures and/or limitations of another independent claim to arrive at amodified independent claim, with the remaining dependent claims in theiroriginal text being read and applied to any independent claim somodified, as if such modified independent claim had been originallyfiled. Accordingly, the presently disclosed invention is intended tocover all such modifications and alterations, and is limited only by thescope of the claims which follow, in view of the contents of thisspecification.

1. A molar tube useful in orthodontic dentistry comprising: a) a baseportion having a first face portion that is adapted to be adhered to amolar tooth, a second face portion, a mesial-distal length dimension,and a vertical dimension; and b) a body portion disposed on said secondface portion of said base portion, said body portion comprising a upperportion and a lower portion, and wherein said body portion furthercomprises: i) a lumen that is adapted to receive an archwire, whereinsaid lumen has an axis which substantially coincides with saidmesial-distal length dimension of said base portion; ii) a bosscomprising a threaded bore that is adapted to receive a setscrew, saidthreaded bore having an axis, wherein said axis of said threaded boreintersects with said mesial-distal length dimension to form an angle ofany degree between 15 degrees and 55 degrees, and wherein the axis ofthe threaded bore intersects with the vertical dimension of the molartube to form an angle of any degree between about 60 and 120 degrees. 2.A molar tube according to claim 1 wherein said lumen has a cross sectionselected from the group consisting of: square, rectangular, or circular.3. A molar tube according to claim 1 wherein said base portion and saidbody portion are collectively part of a single casting.
 4. A molar tubeaccording to claim 1 wherein said upper portion of said body portionfurther comprises a channel having a length dimension that coincideswith said mesial-distal length dimension of said base portion, andwherein said channel is semi-circular in cross section.
 5. A molar tubeaccording to claim 1 wherein said lower portion of said body portionfurther comprises a channel having a length dimension that coincideswith said mesial-distal length dimension of said base portion, andwherein said channel is semi-circular in cross section.
 6. A molar tubeaccording to claim 1 wherein said lower portion of said body portioncomprises a hook arm, which is useful as an anchor point for elastics.7. A molar tube according to claim 1 further comprising a setscrewthreadedly engaged within said threaded bore.
 8. A molar tube accordingto claim 1 wherein said axis of said threaded bore intersects with saidmesial-distal length dimension to form an angle of about 45 degrees. 9.A molar tube useful in orthodontic dentistry comprising: a) a baseportion having a first face portion that is adapted to be adhered to amolar tooth, a second face portion, a mesial-distal length dimension,and a vertical dimension; and b) a body portion disposed on said secondface portion of said base portion, said body portion comprising a upperportion and a lower portion, and wherein said body portion furthercomprises: i) a first lumen having an axis which substantially coincideswith said mesial-distal length dimension of said base portion; ii) asecond lumen having an axis which substantially coincides with saidmesial-distal length dimension of said base portion; iii) a bosscomprising a threaded bore that is adapted to receive a setscrew, saidthreaded bore having an axis which is skew to at least one of said axisof said first lumen or said axis of said second lumen; wherein said axisof said threaded bore intersects with said mesial-distal lengthdimension to form an angle of any degree between 15 degrees and 55degrees, and wherein the axis of the threaded bore intersects with thevertical dimension of the molar tube to form an angle of any degreebetween about 60 and 120 degrees.
 10. A molar tube according to claim 9wherein said first lumen has a cross section selected from the groupconsisting of: square, rectangular, or circular.
 11. A molar tubeaccording to claim 9 wherein said second lumen has a cross sectionselected from the group consisting of: square, rectangular, or circular.12. A molar tube according to claim 9 wherein the cross section of saidfirst lumen is the same as the cross section of said second lumen.
 13. Amolar tube according to claim 9 wherein the cross section of said firstlumen is different from the cross section of said second lumen.
 14. Amolar tube according to claim 9 wherein the cross section of said firstlumen is selected from the group consisting of: square or rectangular;and wherein the cross section of said second lumen is selected from thegroup consisting of: circular or elliptical.
 15. A molar tube accordingto claim 9 wherein said base portion and said body portion arecollectively part of a single casting.
 16. A molar tube according toclaim 9 wherein said upper portion of said body portion furthercomprises a channel having a length dimension that coincides with saidmesial-distal length dimension of said base portion, and wherein saidchannel is semi-circular in cross section.
 17. A molar tube according toclaim 9 wherein said lower portion of said body portion furthercomprises a channel having a length dimension that coincides with saidmesial-distal length dimension of said base portion, and wherein saidchannel is semi-circular in cross section.
 18. A molar tube according toclaim 9 wherein said lower portion of said body portion comprises a hookarm, which is useful as an anchor point for elastics.
 19. A molar tubeaccording to claim 9 further comprising a setscrew threadedly engagedwithin said threaded bore.
 20. A molar tube according to claim 9 whereinsaid axis of said threaded bore intersects with said mesial-distallength dimension to form an angle of about 45 degrees.